α-olefin/conjugated diene copolymers

Abstract

The invention provides olefin polymerization catalyst exhibiting excellent polymerization activities, a process for olefin polymerization using the catalyst, a novel transition metal compound useful for the catalyst, and an α-olefin/conjugated diene copolymer having specific properties. The olefin polymerization catalyst of the invention comprises (A) a transition metal compound of formula (I) or (II), and (B) an organometallic compound, an oranoaluminum oxy-compound or an ionizing ionic compound. The novel transition metal compound of the invention is a compound of formula (I) wherein M is a transition meal atom of Group 3 or 4 of the periodic table; m is an integer of 1 to 3; R 1 is a hydrocarbon group, etc.; R 2 to R 5 are each H, a halogen, a hydrocarbon group, etc.; R 6 is a halogen, a hydrocarbon group, etc.; n is a number satisfying a valence of M; and X is a halogen, a hydrocarbon group, etc.

What is claimed is:  
     
       1. An α-olefin/conjugated diene copolymer having a molecular weight distribution (Mw/Mn) of not more than 3.5, a content of constituent units derived from an α-olefin in the range of 1 to 99.9% by mol and a content of constituent units derived from a conjugated diene in the range of 99 to 0.1% by mol, in which the polymer chain contains 1,2-cyclopentane skeleton derived from the conjugated diene in an amount of less than 0.1% by mol. 
     
     
       2. The α-olefin/conjugated diene copolymer as claimed in  claim 1 , wherein the polymer chain does not substantially contain the 1,2-cyclopentane skeleton derived from the conjugated diene. 
     
     
       3. The α-olefin/conjugated diene copolymer as claimed in  claim 1 , wherein the content of the constituent units derived from the α-olefin is in the range of 50 to 99.9% by mol and the content of the constituent units derived from the conjugated diene is in the range of 50 to 0.1% by mol. 
     
     
       4. The α-olefin/conjugated diene copolymer as claimed in  claim 2 , wherein the content of the constituent units derived from the α-olefin is in the range of 50 to 99.9% by mol and the content of the constituent units derived from the conjugated diene is in the range of 50 to 0.1% by mol. 
     
     
       5. The α-olefin/conjugated diene copolymer as claimed in  claim 1 , wherein the α-olefin is ethylene and/or propylene and the conjugated diene is butadiene and/or isoprene. 
     
     
       6. The α-olefin/conjugated diene copolymer as claimed in  claim 2 , wherein the α-olefin is ethylene and/or propylene and the conjugated diene is butadiene and/or isoprene. 
     
     
       7. The α-olefin/conjugated diene copolymer as claimed in  claim 3 , wherein the α-olefin is ethylene and/or propylene and the conjugated diene is butadiene and/or isoprene. 
     
     
       8. The α-olefin/conjugated diene copolymer as claimed in  claim 4 , wherein the α-olefin is ethylene and/or propylene and the conjugated diene is butadiene and/or isoprene.